Prior-art ignition devices for multi-cylinder internal-combustion engines partly employ mechanical ignition distributors arranged in the secondary circuit of an ignition transformer. The disadvantages of such ignition distributors are well known, particularly with respect to the wear of circuit-breaking elements.
It has already been suggested to associate an ignition transformer with each cylinder adapted to be separately fired, the primary circuits of the ignition transformers being connectable with an ignition capacitor by means of controllable electronic switches which act as an ignition distributor. The control inputs of these switches are connected with a number of sensors corresponding to the sequence of ignition, sensors being activated an initiator synchronously rotating with the crankshaft. This arrangement is not satisfactorily when employed with motors having a great number of cylinders as, e.g. in motors with eighteen cylinders, since in these cases it is extremely complicated to mount and adjust the sensors.